Process of treating leather and product thereof.



ATPENT ornrcn.

ROBERT ATHELSTAN MARR, OF NORFOLK, VIRGINIA, ASSIGNOR TO' GENERAL WATER- PROOFING- C0,, INCORPORATED, F NORFOLK, VIRGINIA, A CORPORATION OF VIRGINIA.

PROCESS OF TREATING LEATHER ANIQ PRODUCT THEREOF.

No Drawing.

a To all whom it may concern:

Be'it known that I, ROBERT ATHELSTAN MARR, a'citizen of the United States, residing at Ghent, Norfolk,.in the county of Norfolk and State .of Virginia, have invented certain new and useful Improvements in Processes of Treating Leather and Product Thereof, of which the following is a specification.

This invention relates to the treatment of leather for the purpose of renderin the sameimpervious to moisture, also for ensifying and hardening the same to a desired degree, also for increasing the wear resisting qualities of the leather, and to preserve the same against rotting and the like.

In my process I am able to completely fill the spaces existing in leather,'even in poor leather such as that made from the hides of old animals, with a material including solid silica in suspension (in a suitable menstruum) said leather thereby" becoming absolutely impervious to moisture, and'unaffelpted by the action of organic acids and the li e. ably that known as diatomaceous earth, which is a very finely divided material, so

7 that 90% of 'the same will pass through a bolting cloth having 40,000 meshes to the square inch. 1

My experiments show that all leathers can be made impervious to moisture and that the process gives life to .theleather and gives it a healthy appearance, increases its tensile strength, also lncreases its resiliency and increases the weight of the leather. The silica being a very hard material also increases the wearing qualities of the leather, for example if the same is used for sole leather,

harness leather or leather belting.

Leather may be treated in a finished .con-

It has heretofore been stated that many varieties of leather are water-proof, but this term has been used in a relative sense only,

since heretofore no leather has been able to 'withstandsoaklng in water for a con- Specification of Letters Patent.

The silica which I employ is prefer- Patented J an. 4, 1916.

Application filed January 14, 1914. Serial No'. 812,026.

siderable time, and then drying, without gettmg hard and more or less brittle, so that the leather after such treatment will be I likely to crack.

In carrying out my processI preferably proceed as follows: The finished or unfinished leather is immersed in a bath prefer- -ably composed of the following materials, and 1n the proportions stated, although these proportions may be varled more orless. arafiin 100 parts; diatomaceous earth 5 to 10 parts, rosin 2' to 10 parts, to which any suitable oil-soluble dye may be added if desired. In certain, cases the rosin may be dispensed with or certain equivalents therefor substituted. The temperature of the bath at, the time of immersion will preferably be about 213 F., and the leather may be immersed in this bath for a time, say from one to two minutes, during which. time, or at the end of which time, the temperature may be allowed to drop to a lower temperature, say 180 to 200 R, if a rather heavy penetration of thematerial is desired. As a modified mode of procedure the temperature of the hot stage may be from 208 to 212 F., and

the temperature may be allowed slowly to.

drop to 180 F., or even lower, if a heavy zimpregnation of the leather is desired.

Leather inlts alr dry condition, ordinarily sired I may use leather containing materially more moisture than these amounts, and thereby am able to secure a very heavy impregnation of the leather, with the impregnating material above referred to.

I call attention to the fact that the silica being in a state of extreme sub-division is carried wherever the melted material is carried, and I am able to thoroughly impregnate every portion of the leather or other hide product, under treatment. v V

The amount of impregnation of the material, will depend upon the amount of moisture in the original leather, the temperature and time of subjection or immersion in the bath, the porosity and physical condition of the leather, which will depend toa eertain extent with a particular leather, upon whether or not the material has been rolled and finished. I am able in this manner to increase the weight of the leather from 12 stances I have been able to increase the weight even more than this, but further increase beyond 25% is generally not advisable or necessary. The rosin will aid in the impregnation of the material by the paraflin, and also produces certain valuable properties in the product, a. g. it' produces adhesion to surfaces, for example the adhesion of belts to pulleys or the prevention of the slipping of the belt over the surface of the pulley. I

I call attention to the fact that theleather may be only partly immersed in the liquid, that is to say one side only of theleather may be immersed, in the liquid, in which case substantially complete impregnation ofthe leather, can be effected. The impregready formation of ice 'upon the surface of the leather thereby preventing slipping.

Since sole leather and some othervarieties of leather are usually sold by weight the increase in weight during the work w1ll very much more than pay for the cost of the in accordance with this process absolutely will not rot in th1s manner, since 1t 1s em tirely protected from atmospheric influences and from moisture. I call attention to the fact that parafiin which is the largest ingredient of my mixture, is entirely insoluble in water, and acts as a preservative for the entrance of water in any form to the impregnated material. p v I desire to call attention to the fact that heretofore various materials have been employed in the impregnation of leather, in combination with volatile solvents such as gasolene and the like, and call attention to the fact that in my process no solvent of this character is employed, since the same is not necessary. By thus doing away with the necessity of a volatile solvent, theexpense 1,1eeeea incident thereto is avoided, and also a more perfect impregnation is secured, than can be obtained when using solvents.

The impregnation of leather or skin, with a mixture comprising parafiin, naphthalene and diatomaceous earth with or without rosin as wellas the product of such treatment, are claimed in my copending appli-.

water, said bath comprising a preservative,

water-proof, impermeableizing agent, comprising diatomaceous earth, and a waterinsoluble fluent carrier comprising a hydrocarbon body which is liquid at a tempera ture of 212 F. and rosin.

2. A process of treating skins and leather, which comprises immersing the same in a bath comprising a preservative, water-proof,

'impermeableizing agent, comprising diatomaceous earth, paraffin and rosin, said bath being maintained at a temperature not materially below the boiling point of water.

3. A process of treating hide products which comprises impregnating the same with a material including parafiin, rosin, and diatomaceous earth said material being at a temperature of about 213 F.

4. A process of treating hide products which comprises impregnating said product by immersing the same in a bath comprising paraffin, rosin, and diatomaceous earth at a temperature of about 213 F and decreasing the temperature of the impregnating material during the process.

5. A process which comprises immersing hide products in a bath comprising diatomaceous earth, paraflin and rosin at a temperature above 212 'F., and thereafter subjecting said materials to a bath having a lower temperature than that employed in said first s ep.

6. As an article of manufacture a hide product impregnated with a material comprising a resolidified, non-reactive impermeableizing agent, liquid at temperatures above 212 F., rosin, and finely divided silicious material having a degree of hardness greater than that of leather, carried by said agent.

7. As a new article of manufacture, a hide product impregnated with a material comprising paraflin, rosin, and a silicious material having a degree of fineness suflicient to be readily carried into the pores of the leather, said silicious material having a hardness greater than that of leather.

' '8, A. hide product impregnated with parafiin, diatomaceous earth, and rosin.

'9. A hide product impregnated with paraflin, a dye soluble therein, diatomaceous earth and. rosin.

10. A process of treating hide products which comprises introducing into the pores thereof, a non-aqueous filling agent comprising a \\-'aterinsoluble, substantially non-volatile, hydrocarbon having a melting point agent comprising diatomaceous earth and a carrier comprising a material which will melt at a temperature below the boiling point of water, which material is insoluble in water.

12. A process of treating leather and skins which comprises impregnating the same with a filling and impermeableizing agent comprising diatomaceous earth and paraflin.

13. A process of treating leather and skins which comprises immersing the same in a bath comprising paraflin and a solid material of suflicient hardness to increase the wear-resisting qualities of leather and of sufiicient fineness to enter the pores, at a temperature somewhat above 212 F.

l-l; A process of treating leather and skins which comprises immersing the-same in a bath comprising paraflin and a solid material containing silica and of sufficient.

fineness to enter thepores, at a temperature somewhat above 212 F.,. and thereafter treating the same with a bath at a temper" ture lower than that'used in said first step. 15. As an article of manufacture a hide product impregnated with a' mixture including diatomaceous earth and a hydrocarbon body.

16. As an article of manufacture a' hide product impregnated with a mixture-includ- 7 ing diatomaceous earth and parafiin.

In testimony whereof I have affixed my signature in presence of two w1tn esses..

{ROBERT- ATHELSTAN' MARR. Witnesses: I I

' I JANEY Horn Mann, A. B. FOSTER. 

